The 802.11 standard is a wireless local area network standard developed by the IEEE (Institute of Electrical and Electronics Engineers, Institute of Electrical and Electronics Engineers) 802.11 working group. An access mechanism in the 802.11 standard is a distributed coordination function (Distributed Coordination Function, DCF). An operating mechanism of the 802.11 DCF is as follows:
When a sending node (transmitter) needs to send data, the sending node sends an RTS (Request to Send, request to send) control packet. The RTS control packet includes an identifier of a receiving node. When the receiving node (receiver) receives the RTS control packet, the receiving node sends a CTS (Clear to Send, clear to send) control packet. The CTS control packet includes an identifier of the sending node. When receiving the RTS control packet and/or the CTS control packet, all other adjacent nodes (other nodes) different from the sending node and the receiving node stop data transmission to ensure data (data) transmission between the sending node and the receiving node. The adjacent nodes start to transmit new data only after receiving an ACK (acknowledgement) signal sent by the receiving node.
However, during practice, it is found that, in the 802.11 DCF access mechanism, all the other adjacent nodes different from the sending node and the receiving node stop data transmission when receiving the RTS control packet or the CTS control packet. Although this prevents the other adjacent nodes different from the sending node and the receiving node from interfering with the data transmission between the sending node and the receiving node, spectrum resource utilization is reduced.